The present invention relates to an automobile condenser electric fan controller adapted to be installed in an automobile for controlling the operation of the automobile's condenser electric fan, which turns off the condenser electric fan automatically as the speed of the automobile surpasses a predetermined critical speed, or turns on the condenser electric fan as the speed of the automobile drops below the critical speed.
Various methods have been disclosed for controlling the operation of the condenser electric fan of an automobile. These methods are still not satisfactory in functions. Drawbacks of these methods are outlined hereinafter respectively.
I. Radiator temperature controlled control method to control the operation of the condenser electric fan according to the temperature of the radiator: As the vehicle is running at a low speed, the performance of the air conditioner and the effect of heat dissipation are getting worse, and the condenser and the evaporator may be damaged easily due to the compression of high pressure.
II. Synchro control methods to synchronously turn on the condenser electric fan as the compressor is started: As the vehicle is running at a high speed, intake current of air is blocked by the condenser electric fan as the condenser electric fan keeps operating, and therefore much energy is wasted.
III. Freon temperature (pressure) controlled control methods to control the operation of the condenser electric fan according to the temperature (pressure) detected by a temperature sensor (pressure sensor). As the vehicle is running at a low speed, the temperature (or pressure) of the freon may be still at a low level and therefore much waiting time is needed before starting the condenser electric fan; if the temperature (or pressure) of the freon has already reached the critical level as the vehicle is running at a low speed, more time and more energy are needed to reduce the temperature (or pressure) by turning on the condenser electric fan, and therefore the generator shall have to work more hard. Further, the condenser and the evaporator may be damaged easily due to the compression of high pressure as the vehicle is running at a low speed. As the vehicle is running at a high speed, the compressor is operated at a high speed to increase the pressure of the freon, and therefore much energy will be consumed to turn off the condenser electric fan.
VI. Vehicle internal temperature controlled control method to turn on/off the condenser electric fan according to the internal temperature of the vehicle. As the vehicle is running from a high speed to a low speed, the condenser electric fan will be turned on only after the internal temperature of the vehicle reaches the critical temperature, therefore there is a time delay, and the driver and the passengers may feel hot before the condenser electric fan is turned on; If the vehicle which is radiated by the direct sunlight for a longth of time is running at a high speed, the condenser electric fan will be turned on to produce a current of air for cooling because the internal temperature of the vehicle is high, therefore intake current of air will be blocked by the condenser electric fan, and much energy will be wasted in turning on the condenser electric fan.
The present invention eliminates the aforesaid drawbacks. It is therefore the principal object of the present invention to provide an automobile condenser electric fan controller for controlling the operation of the condenser electric fan of an automobile automatically according to the speed of the automobile. The control is executed by setting a critical speed, and then detecting the speed of the automobile. As the speed of the automobile surpasses the critical speed, the condenser electric fan is turned off automatically; as the speed of the automobile drops below the critical speed, the condenser electric fan is turned on automatically. Therefore, the present invention saves much energy. Because the freon is constantly maintained at low temperature and low pressure, the performance of the air conditioner of the automobile is maintained at a good condition, and the service life of the condenser and the evaporator is greatly extended.